Weight-Distributing Exoskeleton
[ONE OF THE SIX HIGHEST SCORING TEAMS FOR MAKEATHON 2022]
A weight-distributing exoskeleton intended to be used in manual labor jobs for people with muscle weakness. The prompt for Makeathon 2022 was a solution that will improve accessibility in the workplace. Our solution is meant to distribute weight while heavy-lifting from high-risk injury regions to hips & shoulders. The change in weight distribution is intended to allow those with muscular weakness to be capable of performing heavy lifting tasks. This would allow previously injured workers, non-abled-bodied individuals, muscular-strength-challenged people to perform these strenuous tasks, along with expanding the capacity of weight current workers can lift and promoting healthy lifting technique to reduce injuries. Our solution was made out of laminated laser-cut wood, wooden dowel to reinforce wood, screws, sponges for padding, bungee cords for elastic energy, and spare wood for reinforcement.
Tools
Solidworks
Fusion 360
Laser Cutting
Power Tools
Team
Luca Macesanu
Kate Whitmire
Timeline
October 2022
Competition Time (9 hours)
MAKEATHON 2022
Competition Participants & Judges
Team
Product
DESIGN
We given the prompt at 8 PM the night before the competition and had to submit a design proposal by 8 AM the day of the competition. When brainstorming, we focused on two main types of workplaces: desk jobs & manual labor. We also considered a variety of disabilities such as Tremors, visual-impairments, hearing-impairments, loss of limb, difficulty with fine motor skills, and more. We chose muscular weakness and impairment because we understood that that kind of impairment will restrict individual from performing a job that includes manual labor. We felt we should tackle this issue because (1) it affects many, so it has a large market size; (2) it promotes accessibility for those with disabilities AND abled-bodied individuals with strength-deficiencies; and (3) it is an affordable way for employers to increase the potential candidates for a job.
Over the course of 3 hours, we discussed the mechanics and overall design of our solution. The bungee cords create a tension that aids the user in picking up and holding objects. That tension is applied to the braces beneath the user's forearm and directed over the shoulder onto the hips. The wood "wings" are used to distribute the weight from the tension between the shoulders onto the hips. There is padding in high-load and rigid areas for comfort and a one-inch channel in the wood wing for the cords to sit.
.png)
DEVELOPMENT
After brainstorming the mechanics of the exoskeleton, we spent the night creating the CAD for pieces that we would 3D-Print & Laser Cut. We created a very low-grade cardboard prototype to dimension and fit wood pieces to the natural curve of the back. We used a mix of CAD software depending on purpose. Fusion 360 was utilized to quickly model dimensions & scale of each component relative to each other (along with modeling a motor plate, motor adapters, and a system of gears as we were thought we could use motors for the competition). I used Solidworks to model that parts we wanted to laser cut and created a laser cut template using those parts.
MANUFACTURING
On competition day, we were given from 8 AM to 5 PM to work and manufacture our product. Since we did the CAD overnight, we were able to jump straight on the Laser Cutters and cut our wood parts using a 24" x 30" x 1/4" wood. From there, we were able to laminate our wood pieces together to increase the overall thickness to ensure durability as high loads were applied on the wooden pieces. We added wooden dowels to the laminated wood to reinforce the pieces and assembled the pieces using wood screws. We wanted to strength the stability of the wood structure, so we added supports along the back with spare wood that we shaped using a bandsaw. We created forearm braces using laser-cut wood, sponges for padding, and paracord to link the braces to the bungee cords. We initially had very resistant bungee cords but later changed to bungee cords with a lower spring constant to allow more stretch. These bungees were too long, so we twisted the bungee cords to shorten the overall length. Finally we attached the bungee cords over the shoulders and connected to the base of the wings (near the hips). We added finishing touches such as wooden blocks and zip ties to keep the cords on the track, a belt to prevent rotation & ensure security to the user, and sponges at the lower back and shoulders as padding.
PROBLEM SOLVING & PRESENTATION
Throughout the competition, we had to rapidly problem solve issues such as limited supplies available, keeping the elastic cords on the track, and sufficient supporting of the laminated wood.
The competition broke into judging with around 5 teams in each room. We were given 6 minutes to present our solution and judged based on problem identification, design, execution, feasibility, use of machinery, presentation, and teamwork. Our team was one of six highest-scoring teams chosen to present again in front of the entirety of competition participants and judges.
BEYOND THE COMPETION
For the competition, our solution was purely mechanical due to Makeathon material restrictions and to ensure affordable prices for employers. However, we initially planned on using DC motors, which we later swapped for bungee cords. While we were not allowed to use them for the competition, we were able to find spare DC motors to actuate a gear system. For each side, three DC motors with 3D-printed adapters would connect to a main gear which would rotate to increase the tension of the wire. During our spare time at the competition, we started manufacturing the parts for this system including the 3D-printed adapters, gears, and the gear plate. We are currently working on altering the current product to implement this system post-competition.
.png)
.png)